Otte A P, Moon R T
Department of Pharmacology, University of Washington, School of Medicine, Seattle 98195.
Cell. 1992 Mar 20;68(6):1021-9. doi: 10.1016/0092-8674(92)90074-m.
The restricted ability of embryonic tissue to respond to inductive signals is controlled by a poorly understood phenomenon, termed competence. In Xenopus, dorsal ectoderm is more competent than ventral ectoderm to become induced to neural tissue. We tested whether the Xenopus protein kinase C (PKC) isozymes alpha and beta have a role in neural induction and competence. We found that PKC alpha is predominantly localized in dorsal ectoderm, whereas PKC beta is uniformly distributed. Overexpression of PKC beta conveys a higher propensity for neural differentiation to both dorsal and ventral ectoderm, but their difference in competence remains. However, ectopic expression of PKC alpha elevates the level of neural competence of ventral ectoderm to that of dorsal ectoderm. These data indicate that different PKC isozymes have distinct roles in mediating both neural induction and competence.
胚胎组织对诱导信号作出反应的能力受限，这一现象由一种了解甚少的称作感受态的机制所控制。在非洲爪蟾中，背侧外胚层比腹侧外胚层更容易被诱导形成神经组织。我们测试了非洲爪蟾蛋白激酶C（PKC）同工型α和β在神经诱导和感受态过程中是否发挥作用。我们发现PKCα主要定位于背侧外胚层，而PKCβ则均匀分布。PKCβ的过表达使背侧和腹侧外胚层都具有更高的神经分化倾向，但它们在感受态上的差异依然存在。然而，PKCα的异位表达将腹侧外胚层的神经感受态水平提高到了背侧外胚层的水平。这些数据表明，不同的PKC同工型在介导神经诱导和感受态过程中具有不同的作用。
